December 5, 2021

How does anesthesia work? Why you need to know

Learning how anesthesia works can drastically reduce fear of anesthesia and reduce anxiety and side effects

Anesthesia is the most mysterious branch of medicine. Your anesthesiologist puts you in a medical coma so your surgeon can cut your skin. At the end, your anesthesiologist wakes you up. If done safely, there can be no side effects from this experience. How does anesthesia work so well?

Why do you need to know how anesthesia works?  Because when you know what to expect, the better you can prepare. The better you prepare, the less painful your recovery is!

When you understand how your anesthesia works, the better you can prepare. The better you prepare, the less painful your recovery is.

When you know about your anesthesia, you have less to fear

Nearly 90% of patients have fear of anesthesia before surgery. 25% of patients will postpone surgery from fear of anesthesia. This can have a significant impact on your health! Specifically, patients are afraid of:

  • Awareness under anesthesia.
    • “Will I wake up in the middle of surgery?”
    • “Will I feel pain during surgery?”
  • Complications: brain damage, dying, nausea.
    • “I’m afraid I won’t wake up again.”
  • Pain after surgery.
  • Fear of needles and injections.
    • Some patients call this “needle phobia.” More accurately, it’s trypanophobia.

These fears are serious. In fact, some patients are more afraid of anesthesia than the surgery itself.

The good news, learning about the anesthesia before your surgery can reduce fear. In fact, many patients feel it's very important to meet with their anesthesiologist before surgery.

More preparation → less fear. Less fear → fewer complications.

The more you know, the less the fear. The less the fear, the fewer the complications.

Anxiety and fear are closely related before surgery. They feed off each other in many ways. Importantly, fear and anxiety can lead to many serious complications after surgery:

There are many ways to reduce anxiety - without medications! They involve preparing for your surgery. You want to know what to expect.

Anxiety is common before surgery, but it can also be decreased by learning what to expect. Learning what to expect helps you prepare for surgery and anesthesia.
Anxiety before surgery is very common. Learning how your anesthesia works goes a long way to help reduce that anxiety.

So how does anesthesia work?

There are 4 parts to anesthesia. Each one works affects a different part of your body to keep you safe during surgery:

  1. Amnesia: these medications scramble your memory. This prevents you from remembering the events of surgery.
  2. Loss of consciousness: these medications “turn off” your brain and nervous system. Your anesthesiologist takes over the life-support functions your brain ordinarily would handle.
    • Examples of life-support functions include managing breathing and blood pressure. Your body is often unable to manage these under anesthesia. Your anesthesiologist is there to take over these critical functions!
  3. Movement: some surgeries are highly sensitive to movement, like brain surgery. Moving even a millimeter could be devastating. For these surgeries, your anesthesiologist gives you medications to relax your muscles to keep you safe.
  4. Pain killing: surgery can be painful. Even if you are unconscious, your body still reacts to pain. In fact, your body’s response to extreme pain can be life threatening. Your anesthesiologist manages your body’s pain response while you are asleep to keep you safe.
Anesthesia is the most mysterious branch of medicine.

There are many types of anesthesia, too, like general anesthesia and sedation.

Your anesthesiologist takes care of these 4 parts (above). These 4 parts are included in whatever type of anesthesia is right for you:

  • General anesthesia: you are fully asleep. See my upcoming article explaining general anesthesia.
  • Sedation: you are in a “twilight zone.” You may be partially awake, but you might not remember anything. See my article on twilight sedation.
  • Nerve blocks: see my article explaining what nerve blocks are and how they work.
    • Additionally, you can have a nerve block added to any type of anesthesia.
  • Spinal and epidural anesthesia: these can be combined with other types of anesthesia. See my upcoming article explaining spinal and epidural anesthesia.

Your anesthesia is personalized to you and your type of surgery. There's no "one size fits all."

How can I learn more about how my anesthesia works?

Your anesthesia is highly customized to you and your type of surgery. Learning more about your anesthesia is a powerful step in taking control of your surgery. You can reduce your pain and other side effects by "taking the driver seat." Your most trusted source will be your anesthesiologist!


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Van den Bosch et al. Does Measurement of Preoperative Anxiety Have Added Value for Predicting Postoperative Nausea and Vomiting?, Anesthesia & Analgesia: May 2005 - Volume 100 - Issue 5 - p 1525-1532

Spalding, Nicola Jane. "Reducing anxiety by pre‐operative education: Make the future familiar." Occupational therapy international 10.4 (2003): 278-293.

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